A. Field of the Invention
The present invention relates generally to the field of slide projector apparatus and more particularly to an improved slide transfer and shutter control arrangement for slide projector apparatus.
B. Description of the Prior Art
Various slide transfer and shutter control arrangements have been proposed by the prior art to control the transfer of slides between a slide tray and a projection station and to control the opening and closing of a shutter to selectively project the slide at the projection station. For example, slide transfer and shutter control arrangements are disclosed in the following U.S. Pat. Nos.: 4,200,368; 3,334,544; 3,411,845; 3,876,298; 3,353,443; 3,138,062; 4,130,353; 3,180,212; 2,871,760; 3,412,495; 2,978,823; 3,228,132; 3,023,669; 3,644,029; 3,572,920; 3,938,886; 3,644,028; 3,856,391; 3,721,494; 3,677,631; 3,924,942; 3,907,414; 3,895,864; 3,408,139; 3,343,454; and 3,652,155.
Specifically, slide transfer and shutter control arrangements utilizing a slide sensor that functions to assist in the control of a shutter are disclosed in the aforementioned U.S. Pat. Nos. 4,200,368; 3,876,298; 3,411,845; 3,138,062; 3,334,544; 2,978,823; 3,180,212; and 4,130,353.
While the arrangements of the prior art are generally suitable for their intended use, it would be desirable to provide an improved slide transfer and shutter control arrangement that utilizes a more positive acting slide sensor and a more simplified shutter control arrangement.
For example, the aforementioned U.S. Pat. No. 4,200,368 to Househnecht utilizes a pivotally mounted slide feeler 113 and latch member 110 and utilizes shutter control elements 90, 98 interacting with the latch member 110 at 116 to control operation of the shutter. While this arrangement could apparently be suitable for its intended use, it would be desirable to provide an improved slide transfer and shutter control arrangement that avoids the use of a pivotally mounted slide sensor and provides more positive slide sensing action and further provides direct shutter control by the slide sensor in a simplified arrangement.